Cunliffe Group

Microbial life defines most of the biogeochemical properties of our oceans. The interactions that take place between marine biogeochemical cycles and marine microorganisms are profound.

"The role of the infinitely small in Nature is infinitely great" - Louis Pasteur

Microorganisms are the most abundant components of marine ecosystems, and have a diverse array of metabolic functions that control biogeochemical cycles and maintain the earth system. Connecting microbial phylogenetic diversity and metabolic capability with biogeochemical processes is vital to achieve a comprehensive understanding of marine ecosystem structure and functioning

The Cunliffe Research Group at the MBA is focused on understanding the underpinning mechanisms, both ecological and physiological, by which microorganisms sustain marine biogeochemical cycles and other ecosystem services. The multidisciplinary research integrates contemporary omics approaches with analytical biogeochemical techniques and classic microbiological methods, combining field-based observation of complex microbial assemblages and laboratory-based experiments using model microorganisms.

Below are examples of current and recent research projects that illustrate the approach of the Cunliffe Group, combining both field-based and laboratory-based microbial biology and ecology.......

Carbon monoxide oxidation in the abundant Marine Roseobacter Clade (MRC). Annotation of multiple MRC genomes has revealed that an abundance of carbon monoxide dehydrogenase cox genes are present, implying a role for the MRC in marine CO cycling. I have established the link between cox genes and metabolic function (i.e. CO oxidation). cox genes fall into two different forms; form I and form II. Only MRC strains with form I cox genes can oxidise CO (Cunliffe 2011). Even though Ruegeria pomeroyi expresses CO dehydrogenase and oxidises CO, CO has no effect on growth or cellular metabolite profiles (Cunliffe 2013). These results are important because they validate ecosystem models that propose, even though bacterioplankton CO oxidation is biogeochemically significant, it has an insignificant effect on bacterioplankton productivity.

Purine degradation and nitrogen regeneration in Ruegeria pomeroyi. Using transcriptomics (RNASeq, Illumia Hiseq), I have established the metabolic pathways active in R. pomeroyi during xanthine degradation. This is the first study to characterise purine utilisation in a marine bacterium. The transcriptome-deduced pathway indicates that ammonia is produced during xanthine catabolism (Cunliffe 2016). Ammonia is an important source of regenerated nitrogen that sustains phytoplankton productivity throughout the summer once nitrate has been depleted (Ward et al 2011).

MARINe-DNA: Development and application of eDNA tools to assess the structure and function of coastal sea ecosystems

The MARINe-DNA project will test the overarching hypothesis that marine-derived environmental DNA (eDNA) is a biodiversity proxy that can be used to inform our understanding of marine biodiversity and ecosystem structure/function relationships. The project will be split into three phases that...

Oil spills that release harmful petroleum hydrocarbons into the marine environment can be cleaned up in several ways. These include sponge-like sorbents that absorb oil, dispersants that chemically break down oil, and microorganisms that biologically degrade oil by consuming it as an energy...

Kim is currently carrying out research at the Marine Biological Association UK for her PhD, entitled: The marine microbial biogeochemistry of carbon monoxide – connecting biodiversity with ecosystem function.

The Marine Biological Association conducts, promotes and supports scientific research into all aspects of life in the sea. We're working with our ever-growing membership to provide a clear and independent voice on behalf of the marine biological community